v21.58

Finally replaced the default diesel train locomotive sounds!
The sound includes much more detail than the default sound, including:
- Brake squeals when stopping.
- Improved sound transitions of idle, acceleration, and deceleration.
- Completely reworked soundset of the engine, with a fuller spectrum of frequencies.
- Most importantly, realistic volume fall-off. It will only be loud in close proximity.

v21.57

After an amazing discovery, the reefer / refrigerated trailer sounds have been updated to include a highly requested change:
By extending the functionality of the wind sounds, the reefer trailer sound can now play while driving.

It's still a workaround since it's not a standard feature in the game yet, but until then we can pioneer the sound this way!
Previous trailer mods that activate the reefer sounds from this pack in 1.41 are forwards compatible with this update.
This feature is optional and requires activation by a reefer sound addon or trailer mod to enable the sound.

Important information to take note from this new change:

- This relies on the wind sound to "carry" the reefer sound once you drive, so other wind sound mods won't be compatible.
- "Noise of the flowing air" must be activated in the Audio settings.
- Due to the way the wind sounds are optimized in game, it cannot sustain the reefer sound at 0 km/h for long.
- The reefer sounds should kick back in once you set off, however.
- The Trailer Noise slider controls the sound volume of the reefer startup noise and sound loop of a new cycle.
- The Truck Noise slider controls the sound volume of the reefer sound loop when driving.
- It is recommended to have both sliders at the same volume (50%) for consistency.
- If you want to take a break and keep the reefer idling such as when you are at a truck stop:
Simply disconnect and reconnect the trailer to reactivate the cycle.
This will allow you to hear the reefer when you are idle or parked. It can be a relaxing white noise this way.

Regarding what the refrigerated trailer sound can be confirmed to work with:

✔️ Freight Market: Confirmed to work.
✔️ External Contracts: Confirmed to work.
✔️ Quick Jobs: Can work, but you need to disconnect and reconnect the trailer to start the cycle.
❌ Ownable Trailers: Not applicable.

v21.56

Implemented smoother transitions for rain sound intensity.
New variations in sound of the standalone air horn (does not apply to the in-cabin view).

With certain camera views, the standalone air horn can be used creatively to output a different sound.
This includes:
1. Quickly using the horn
2. Laying on the horn
3. Using 1 air horn rather than 2
4. Taking advantage of the doppler effect, tunnels, or from being further away from your truck

Ending of each trailer brace rotation sound now has another variation.
Minor adjustment to trailer brace rotation sound for lifting trailer leg.
Improved consistency for trailer brace rotation sound volume for the reefer trailer sound addons.
Optimizations for sound files without quality loss.
Engine sounds added for the Volvo XC90 (1st generation, pre-facelift) in AI traffic.

v21.52

1 new default air brake sound variant, also applied to AI traffic trucks.

v21.51

Sound of tire whine from the exterior view is now also simulated when you look outside the window at high speeds.
Improved low-range of open window wind sounds.
Increased mid-range of sleeper line sound dependent on current speed.

v21.50

Tweaked high speed tire sound (interior view).
Improved volume curves for window wind sounds.
Increased mid-range of sleeper line sound.

v21.49

Quietened interior tire sound for asphalt and sleeper line terrains.
Improved open window experience with better sound mix and quieter wind.
Improved fall-off for Boeing 737 flyby sound.

v21.48

Improved air brake sounds can now sometimes be heard when any bus or truck in AI traffic comes to a stop.
Replaced the air gear sound for AI traffic trucks. It can sometimes be heard when the AI traffic truck changes gear.
Replaced 1 default air brake sound effect.
Added 1 default air brake sound effect.
Quietened Boeing 737 taxiing sound in scenarios where there are multiple planes taxiing in the same airport.
Reduced range of Boeing 737 taxiing sound.

v21.47

New version of trailer brace rotation sounds.
3D positioned trailer brace rotation sounds.
Engine sounds added for the Mercedes-Benz C-Class (W204 2008) in AI traffic.
Minor sound mix tweaks for default AI car tire sounds.
Optimizations for sound files without quality loss.

v21.46

Added 1 new sound variant for when coupling trailer.
3D positioned and enhanced the trailer coupling sounds.
Engine and horn sounds added for the Honda Accord (8th generation) in AI traffic.
Horn sound added for the Audi A6 (C6 generation) in AI traffic.
Optimizations for sound files without quality loss.